BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention relates to a method and an apparatus for producing binary image
data of a halftone dot image from multi-digital image data of a contone image (or
a continuous tone image).
Description of the Prior Art
[0002] In color printing process, direct scanners having a dot generator are widely used
for electronically performing dot generation operation, by which contone images are
converted into halftone dot images. Dot generators include a hardware type and a software
type.
[0003] A hardware dot generator includes a specific electronic circuit with a comparator
and a screen pattern memory. The screen pattern memory stores a basic pattern or patterns
having threshold level data. The hardware dot generator compares a multi-digital image
signal with the basic pattern or patterns with the comparator thereof and forms halftone
dots corresponding to the level of the image signal.
[0004] Although the hardware dot generator has the advantage of high speed processing, it
lacks versatility to form halftone dots for special conditions other than standard
halftone dots. For example, the hardware dot generator cannot form halftone dots having
rather complicated shapes.
[0005] GB-A-2 117 208 discloses an apparatus for reproducing a composite picture from an
original picture and a scanned character picture which comprises software dot generating
means and hardware dot generating means, the picture signals being digitized by analog-to-digital
converters. It should be avoided to enlarge capacity of memory devices when increasing
the resolving power of scanned characters for editing purposes.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is to provide a dot generating apparatus and a
dot generating method which will have a flexibility to form special halftone dots
for a special condition and ordinary halftone dots at relatively high speed.
[0007] The present invention is directed to a method, according to claim 9, of and an apparatus,
according to claim 1, for forming a halftone image from a contone image, the apparatus
comprising:
multi-digital image data supplying means for supplying multi-digital image data representing
the contone image;
hardware dot generating means having an eiectronic circuit including a comparator
and a first pattern memory for producing binary image data representing said halftone
image in response to a level of the multi-digital image data, the first pattern memory
storing first basic pattern data for dot formation consisting of a plurality of threshold
levels, the hardware dot generating means performing the producing by comparing the
first basic pattern data with the multi-digital image data with the comparator for
each pixel;
software dot generating means having an electronic circuit including a second pattern
memory, a program memory and a processor, for producing binary image data representing
said halftone image in response to a level of the multi-digital image data, the second
pattern memory storing second basic pattern data consisting of function data, the
program memory storing program for calculating binary image data on the basis of multi-digital
image data and the function data, the processor executing the program to produce binary
image data according to the program; and
selection means for selecting one of the hardware dot generating means and the software
dot generating means, and activating the selected means.
[0008] Preferably, the first pattern memory is a read only memory, and the second pattern
memory is a random access memory.
[0009] The apparatus comprises data input means for inputting a halftone-dot type data indicating
a type of half-tone dots; and the selection means comprising: judging means for judging
whether the halftone-dot type data corresponds to the first basic pattern data or
the second basic pattern data; and selective activation means for activating the hardware
dot generating means when the halftone-dot type data corresponds to the first basic
pattern data and activating the software dot generating means when the halftone-dot
type data corresponds to the second basic pattern data.
[0010] In addition, the first and second pattern memories store plural sets of first pattern
data and plural sets of second pattern data, respectively; and one of the hardware
and software dot generating means activated by the selective activation means performs
the producing binary image data on the basis of a designated pattern data in the first
and second pattern memories designated by the halftone-dot type data.
[0011] The apparatus further comprises: image region specifying means for specifying plural
image regions in the contone image; and wherein the selective activation means activates
one of the hardware and software dot generating means for each of the plural image
regions according to the halftone-dot type data assigned to each of the plural image
regions.
[0012] Moreover, the apparatus comprises: image editing means for editing the contone image
including a character, a graphic, and a picture element, producing the multi-digital
image data representing the contone image, and supplying the multi-digital image data
to the multi-digital image data supplying means to be stored therein; and recording
means for recording a halftone dot image on the basis of the binary image data generated
by one of the hardware dot generating means and the software dot generating means.
[0013] The multi-digital image data includes a page description language expressing locations,
directions, and sizes of the character, graphic, and picture element in the contone
image.
[0014] The multi-digital image data supplying means further includes a multi-digital frame
memory.
[0015] These and other objects, features, aspects and advantages of the present invention
will become more apparent from the following detailed description of the present invention
when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In the accompanying drawings:
Fig. 1 is a block diagram illustrating the basic structure of an apparatus according
to the present invention;
Fig. 2 is a block diagram illustrating an image editing system including a halftone
dot image generating apparatus embodying the present invention;
Fig. 3 is a block diagram illustrating the structure of the hardware dot generator
of Fig. 2;
Fig. 4 is a flowchart of dot generation executed by the CPU of Fig. 2;
Fig. 5 is an explanatory view illustrating dot generation by applying a software;
and
Fig. 6 is an explanatory view illustrating image regions in an one-page-image.
DETAILED DESCRIPTION OF THE INVENTION
[0017] Fig. 1 is a block diagram schematically showing the structure of an image processing
apparatus according to the present invention.
[0018] The image processing apparatus includes a multi-digital image data supplying unit
M1, a hardware dot generating unit M2, a software dot generating unit M3, and a selector
unit M4.
[0019] The multi-digital image data supplying unit M1 stores multi-digital image data representing
a contone image.
[0020] The hardware dot generating unit M2 is composed of specific electronic circuits with
a comparator and a pattern memory, in which a first basic pattern or patterns for
dot formation are previously stored. The comparator of the hardware dot generating
unit M2 compares the multi-digital image data with the first basic pattern or patterns
and generates binary halftone-dot image data according to the level of the multi-digital
image data.
[0021] The software dot generating unit M3 includes a processor for processing multi-digital
image data according to predetermined procedure and a memory for storing a program
for generating a second basic pattern or patterns for dot formation. The software
dot generating unit M3 compares the multi-digital image data with the second basic
pattern or patterns and generates binary halftone-dot image data according to the
level of the multi-digital image data.
[0022] The selector unit M4 alternatively selects and activates one of the hardware dot
generating unit M2 and the software dot generating unit M3.
[0023] In this image processing apparatus, multi-digital image data representing a contone
image, stored in the multi-digital image data supplying unit M1, is converted into
binary halftone-dot image data. The data conversion is performed by one of the hardware
dot generating unit M2 and the software dot generating unit M3 alternatively selected
by the selector unit M4.
[0024] Fig. 2 is a block diagram illustrating an image editing system including a halftone
image generating apparatus embodying the present invention.
[0025] The image editing system includes terminal processors 1 and 3 and an integrated image
recorder 5, which are connected to one another through a local area network (LAN).
[0026] Each of the terminal processors 1 and 3 is a microcomputer or a work station. The
terminal processor 1 or 3 outputs image data representing a picture image as well
as a PDL program written in a page description language, which represents a page of
an integrated image including characters, graphics, and picture elements edited by
an operator. The page description language is generally abbreviated as PDL, and is
available with the name of 'Postscript', 'Interpress', or 'DDL'.
[0027] The integrated image recorder 5 receives the PDL program and image data of a picture
element output from the terminal processor 1 or 3 and generates an integrated image.
The integrated image recorder 5 includes: a front end interface 11 for transmitting
data into and from the terminal processors 1 and 3; a CPU 13 for executing various
application programs; a ROM 15 for storing the application programs and initial data
required for the processing by the CPU 13; a RAM 17, which various data are temporarily
written in and read from for the processing by the CPU 13; a first magnetic disk unit
19 for storing preset character fonts; and a second magnetic disk unit 21 for storing
the image data.
[0028] The integrated image recorder 5 further includes: a multi-digital frame memory 23
for temporarily storing multi-digital image data; a hardware dot generator 25 for
converting the multi-digital image data into binary image data representing a halftone
dot image; a binary frame memory 27 for storing the binary image data; and an output
scanner 29 for recording the halftone dot image according to the binary image data
onto a film or the like. All the constituents above are interconnected through an
internal bus IB.
[0029] In place of the binary frame memory 27, another memory can be installed in which
compressed image data of the binary image data, such as run-length data, are stored.
[0030] The integrated image recorder 5 receives the PDL program and image data of a picture
element supplied from the terminal processor 1 or 3 and temporarily stores the image
data in the second magnetic disk unit 21. The image recorder 5 then generates respective
images of characters, graphics, and picture elements based on the PDL program and
the image data, and develop the images thus generated into raster data, respectively,
in the multi-digital frame memory 23. In detail, the image recorder 5 compares part
of the PDL program expressing a character with the character fonts stored in the first
magnetic disk unit 19 and generates an image representing the outline of the character;
generates a graphic image based on another part of the PDL program expressing the
graphic; and generates an image of a picture element based on still another part the
PDL program expressing the picture element and on image data read out from the second
magnetic disk unit 21. The images thus generated are developed into raster data in
the multi-digital frame memory 23.
[0031] The raster data (hereinafter referred to as multi-digital image data) can be then
converted into binary image data of a halftone dot image by the hardware dot generator
25, which is composed of specific electronic circuits. The binary image data is stored
in the binary frame memory 27. The binary image data is then supplied from the output
scanner 29 to form the halftone dot image on the film.
[0032] The data conversion from multi-digital image data to binary image data can be also
executed by the CPU 13 according to a predetermined program stored in ROM 15.
[0033] The structure of the hardware dot generator 25 and the dot generating procedure executed
by the CPU 13 are explained below in detail.
[0034] The hardware dot generator 25, as shown in Fig. 3, includes a screen pattern memory
(or SPM) 25a for storing basic pattern data required for dot formation, first address
counter 25b for specifying an address in the SPM 25a, a second address counter 25c
for specifying an address in the multi-digital frame memory 23, and a third address
counter 25d for specifying an address in the binary frame memory 27. The hardware
dot generator 25 further includes a comparator 25e for comparing image data supplied
from the multi-digital frame memory 23 with the basic pattern data supplied from the
SPM 25a; and a controller 25f for outputting control signals to the address counters
25b, 25c, and 25d, the multi-digital frame memory 23, and the binary frame memory
27. The SPM 25a is a ROM. The SPM 25a stores plural sets of the basic pattern data
representing plural halftone-dot patterns which have relatively simple shapes and
which are frequently used in ordinary image reproduction or printing: such as square
dots, chain dots, round dots, and brick dots.
[0035] The hardware dot generator 25 operates as follows: On receiving a start-up signal
and image region data, which defines an image region subjected to the dot formation,
from the CPU 13, the controller 25f supplies the image region data to the second address
counter 25c and also supplies a read signal instructing data-output operation to the
multi-digital frame memory 23. The second address counter 25c outputs an address signal
specifying an address in the multi-digital frame memory 23. The multi-digital frame
memory 23 receives the address signal and the read signal and then supplies image
data specified by the address signal to the comparator 25e.
[0036] While supplying the image region data to the second address counter 25c, the controller
25f also supplies the image region data to the first and the third address counters
25b and 25d. The first address counter 25b outputs an address signal specifying an
address in the SPM 25a. The SPM 25a receives the address signal and then outputs a
value of the basic pattern data specified by the address to the comparator 25e.
[0037] Each value of the basic pattern data stored in the SPM 25a includes a plurality of
threshold levels with respect to a pixel and is to be compared with the multi-digital
image data. The basic pattern data is defined, for example, in a square region whose
side has a length of tens of pixels. The basic pattern data is repeatedly assigned
to an image plane such that the square regions are arranged to cover all over the
image. In other words, a synchronized threshold level pattern is assigned on one image
plane. While taking into consideration of the repetitional assignment of the basic
pattern data, the address signal for the SPM 25a is made to correspond to the address
signal for the multi-digital frame memory 23.
[0038] The comparator 25e compares the image data supplied from the multi-digital frame
memory 23 with basic pattern data supplied from the SPM 25a. When the level of the
image data is no less than the level of the basic pattern data, the comparator 25e
supplies binary data having a value of "1" to the binary frame memory 27 at the address
specified by the address signal from the first address counter 25b. On the other hand,
when the level of the image data is less than the level of the basic pattern data,
binary data having a value of '0' is given to the binary frame memory 27. Consequently,
binary image data representing an image consisting of halftone dots in such a size
responsive to the level of the multi-digital image data, is stored in the binary frame
memory 27.
[0039] The dot generating process by the CPU 13 is explained along with the flowchart of
Fig. 4. A program of the flowchart stores in ROM 15.
[0040] At step 100, the CPU 13 reads halftone dot information specifying a dot shape expressed
in a dot shape code, a screen ruling, and a screen angle, each of which can be selected
by an operator with an operation panel or a mouse. Selectable halftone dots include
square dots, round dots, chain dots, brick dots, triangle dots, honeycomb dots, grain
dots, and concentric circular dots.
[0041] The CPU 13 may receive the halftone dot information from the RAM 17 at step 100 when
it is previously included in the PDL program, which is supplied from the terminal
processors 1 and 3 and stored in the RAM 17. The dot shape is expressed in a functional
data in the PDL program. Alternatively, an operator can directly input the halftone
dot information as functional equations or numerals with a keyboard (not shown).
[0042] At step 110, it is judged whether a halftone dot specified by the halftone dot information
is equal to that of the basic pattern data in the SPM 25a of the hardware dot generator
25. The RAM 17 stores a table of flags showing whether or not the basic pattern data
corresponding to each dot shape code is stored in the SPM 25. The CPU 13 compares
the dot shape code obtained at step 100 with the table of flags for the judgment.
[0043] When a halftone dot specified by the halftone dot information corresponds to one
of the basic pattern data in the SPM 25a, the procedure proceeds to step 120, at which
the CPU 13 outputs a start-up signal and image region data, which defines an image
region subjected to the dot formation to the hardware dot generator 25. The image
region data defines an address region in the multi-digital frame memory 23 and in
the SPM 25a. The CPU 13 also outputs a signal to indicate one of the plural sets of
the basic pattern data in the SPM 25a. The hardware dot generator 25 is accordingly
activated and converts the multi-digital image data into binary image data according
to the selected basic pattern data. The binary image data thus obtained is stored
in the binary frame memory 27. Then the procedure is completed.
[0044] On the other hand, when the halftone dot specified by the halftone dot information
does not corresponds to one of the the basic pattern data in the SPM 25a at step 110,
the procedure proceeds to step 122, at which a variable x is set at zero. The variable
x represents a coordinate (or an address) in a subscanning direction of multi-digital
image data developed as raster data. At the next step 124, a variable y is set at
zero. The variable y represents a coordinate in a main scanning direction of multi-digital
image data.
[0045] The variable x is increased by one at step 130, and the variable y is increased by
one at step 140.
[0046] At step 150, the CPU 13 reads out multi-digital image data A(x,y) stored at an address
defined by the values of x and y in the multi-digital frame memory 23.
[0047] At step 160, a threshold level F(x,y) used for the dot formation is calculated from
a functional equation specified by the dot shape code which is input at step 100.
The RAM 17 stores in advance a table of functional equations each of which represents
a shape of a halftone dot. The CPU 13 searches for one of the functional equations
that corresponds to the dot shape code, and calculates the threshold level F(x,y)
from the functional equation. The threshold level F(x,y) corresponds to the function
data in the present invention. In general, the function data is a set of values of
a functional equation which is designated by the dot shape code and whose value depends
on the position in an image plane.
[0048] For example, when the desired halftone dots on an image form concentric circles in
shape, as shown in Fig. 5, the threshold level F(x,y) representing the halftone dot
shape is calculated from the following equation (1):

where k0 is a constant and r0 is a distance corresponding to a cycle of the dot shape
as shown in the lower part of Fig. 5. A variable r is determined from the values of
x and y as follows:

where x
0 and y
0 are coordinates of the center of the concentric circles.
[0049] When the halftone dot information input at step 100 includes a functional equation
expressing a shape of halftone dots, the threshold level F(x,y) is determined from
the functional equation, which is stored in the RAM 17 at step 160.
[0050] At step 170, the multi-digital image data A(x,y) input at step 150 is compared with
the threshold level F(x,y) calculated at step 160. When the image data A(x,y) is equal
to or greater than the threshold level F(x,y), the procedure proceeds to step 180
at which data having a value of "1" is written in the binary frame memory 27 at a
location defined by the values x and y. In other words, the value of the binary image
data B(x,y) is set at one. On the other hand, when A(x,y) is less than F(x,y) at step
170, the procedure proceeds to step 190 at which the value of the binary image data
B(x,y) is set at zero.
[0051] Step 180 and step 190 are followed by step 200, at which it is judged whether the
variable y has reached to its maximum value ymax. When the variable y is less than
ymax, the program returns to step 140 and repeats the processing from step 140 to
step 200. When the variable y is equal to or greater than ymax at step 200, the processing
proceeds to step 210 at which it is judged whether the variable x has reached to its
maximum value xmax. When the variable x is less than xmax, the processing returns
to step 124 and the variable y is initialized again. Steps 130 through 210 are then
repeated for the next scanning line.
[0052] When the variable x is equal to or greater than xmax at step 210, the processing
exits the routine.
[0053] As described above, in this embodiment, the hardware dot generator 25 forms halftone
dots having ordinary shapes, e.g., squares, rounds, chains, or bricks, frequently
used in ordinary reproduction or printing; thus, high-speed dot formation is accomplished
by the hardware dot generator. On the other hand, the software dot formation by the
CPU 13 forms halftone dots having complicated shapes, e.g., grains or concentric circles.
The software dot formation has another advantage of forming different types of halftone
dots in one page, such as those having different shapes, different screen rulings,
or different screen angles. Thus, the software dot formation provides more flexibility
in forming various halftone dots than the hardware dot formation.
[0054] In the above embodiment, the multi-digital image data supplying unit M1 shown in
Fig. 1 corresponds to the multi-digital frame memory 23, and the hardware dot generating
unit M2 corresponds to the hardware dot generator 25. Further, the software dot generating
unit M3 corresponds to the dot formation processing executed by the CPU 13, and the
selector unit M4 corresponds to step 110 shown in Fig 4.
[0055] Although multi-digital image data are temporarily stored in the multi-digital frame
memory 23 and then processed in the above embodiment, image data supplied from the
terminal processors 1 can be developed into raster data by the CPU 13 and directly
converted into binary halftone-dot image data. That is, the multi-digital image data
developed into raster data by the CPU 13 can be directly supplied to the hardware
dot generator 25 or directly processed according to the dot formation program carried
out by the CPU 13.
[0056] In a one-page image to be recorded by a recording scanner 29, some part of the image
may be processed by the hardware dot formation and the other part by applying the
software dot formation. Fig. 6 illustrates a one-page image including plural image
regions. Each of the plural image regions R1, R2, R3, and R4 can be processed by one
of the hardware and the software dot formation. Further, the image regions can be
processed with respective types of halftone dots, such as those having different shapes,
different screen rulings, and different screen angles. In these cases, the steps from
100 through 210 shown in Fig. 4 are performed for each image region.
1. An apparatus for forming binary image data of a halftone dot image from multi-digital
image data of a contone image comprising:
(a) multi-digital image data supplying means (M1) for supplying multi-digital image
data representing said contone image;
(b) hardware dot generating means (M2;25) having an electronic circuit including a
comparator (25e) and a first pattern memory (25a) for producing binary image data
representing said halftone image in response to a level of said multi-digital image
data, said first pattern memory (25a) storing first basic pattern data for dot formation
consisting of a plurality of threshold levels, said hardware dot generating means
(M2;25) performing said producing by comparing said first basic pattern data with
said multi-digital image data with said comparator (25e) for each pixel;
(c) software dot generating means (M3) having an electronic circuit including a second
pattern memory (17), a program memory (17) and a processor (13), for producing binary
image data representing said halftone image in response to a level of said multi-digital
image data, said second pattern memory storing second basic pattern data consisting
of function data, said program memory storing a program for calculating binary image
data on the basis of multi-digital image data and said function data, said processor
executing said program to produce binary image data; and
(d) selection means (M4) selecting one of said hardware dot generating means (M2;25)
and said software dot generating means (M3), and activating the selected means.
2. An apparatus in accordance with claim 1, wherein
said first pattern memory (25a) is a read only memory, and said second pattern
memory is a random access memory (17).
3. An apparatus in accordance with claim 1 further comprising:
data input means for inputting a halftone-dot type data indicating a type of half-tone
dots; and wherein
said selection means comprising:
judging means for judging whether said halftone-dot type data corresponds to said
first basic pattern data or said second basic pattern data; and
selective activation means for activating said hardware dot generating means (M2)
when said halftone-dot type data corresponds to said first basic pattern data and
activating said software dot generating means (M3) when said halftone-dot type data
corresponds to said second basic pattern data.
4. An apparatus in accordance with claims 1-3, wherein
said first and second pattern memories (25a, 17) store plural sets of first pattern
data and plural sets of second pattern data, respectively; and
one of said hardware and software dot generating means (M2, M3) activated by said
selective activation means performs said producing binary image data on the basis
of a designated pattern data in said first and second pattern memories (25a, 17) designated
by said halftone-dot type data.
5. An apparatus in accordance with claims 1-4 further comprising:
image region specifying means for specifying plural image regions in said contone
image; and wherein
said selective activation means activates one of said hardware and software dot generating
means (M2, M3) for each of said plural image regions according to said halftone-dot
type data assigned to each of said plural image regions.
6. An apparatus in accordance with claims 1-5 further comprising:
image editing means for editing said contone image including a character, a graphic,
and a picture element, producing said multi-digital image data representing said contone
image, and supplying said multi-digital image data to said multi-digital image data
supplying means; and
recording means for recording a halftone dot image on the basis of said binary image
data generated by one of said hardware dot generating means (M2) and said software
dot generating means (M3).
7. An apparatus in accordance with claims 1 and 6, wherein
said multi-digital image data of said multi-digital image data supplying means
includes a page description language expressing locations, directions, and sizes of
said character, graphic, and picture element in said contone image.
8. An apparatus in accordance with claims 1, 6 and 7, wherein
said multi-digital image data supplying means (M1) includes a multi-digital frame
memory.
9. A method of forming binary image data of a halftone dot image from multi-digital image
data of a contone image comprising the steps of:
(a) preparing multi-digital image data representing said contone image for each pixel;
(b) preparing a hardware dot generator (M2;25) having an electronic circuit including
a comparator (25e) and a first pattern memory (25a) for storing a first basic pattern
data for dot formation consisting of a plurality of threshold levels, and a software
dot generator (M3) having an electronic circuit including a program memory (17), a
processor (13) and a second pattern memory (17) for storing a second pattern data
consisting of function data;
(c) selecting one of said hardware dot generator (M2;25) and software dot generator
(M3); and
(d) activating the selected generator, whereby said hardware dot generator (25) compares
said first basic pattern data with said multi-digital image data with said comparator
(25e) for each pixel to produce binary image data when said hardware dot generator
(25) is selected, and said software dot generator (M3) calculates binary image data
representing said halftone image on the basis of multi-digital image data and said
second pattern data with said processor according to a program stored in said program
memory (17) when said software dot generator (M3) is selected.
10. A method in accordance with claim 9, wherein
said first pattern memory (25a) is a read only memory, and said second pattern
memory is a random access memory (17).
11. A method in accordance with claims 9 and 10 comprising prior to said step (d) a step
of:
inputting a halftone-dot type data indicating a type of halftone-dots; and wherein
said step (d) comprising the steps of:
(d-1) judging whether said halftone-dot type data corresponds to said first basic
pattern data or said second basic pattern data; and
(d-2) activating said hardware dot generator (M2) when said halftone-dot type data
corresponds to said first basic pattern data and activating said software dot generator
(M3) when said halftone-dot type data corresponds to said second basic pattern data.
12. A method in accordance with claims 9 to 11, wherein
said first and second pattern data includes plural sets of first pattern data and
plural sets of second pattern data, respectively; and
at said step (d), an activated dot generator (M2, M3) produces said binary image data
on the basis of a designated pattern data in said first and second pattern data designated
by said halftone-dot type data.
13. A method in accordance with claims 9 to 12 comprising between said steps (b) and (c)
a step of:
specifying plural image regions in said contone image; and wherein
at said step (d), one of said hardware and software dot generators (M2, M3) is activated
for each of said plural image regions according to said halftone-dot type data assigned
to each of said plural image regions.
14. A method in accordance with claims 9 to 13, wherein
said step (a) comprising a step of editing said contone image including a character,
a graphic, and a picture element to produce said multi-digital image data; and
said method further comprising a step of recording a halftone dot image on the basis
of said binary image data generated by one of said hardware dot generator (M2) and
said software dot generator (M3).
15. A method in accordance with claim 14, wherein
said multi-digital image data includes a page description language expressing locations,
directions, and sizes of said character, graphic, and picture element in said contone
image.
1. Vorrichtung zur Bildung binärer Bilddaten eines Halbtontonbildes aus multidigitalen
Bilddaten eines Kontonbildes, mit
(a) Multidigitalbilddaten-Liefermitteln (M1) zum Liefern multidigitaler Bilddaten,
die das Kontonbild darstellen,
(b) Hardware-Punkterzeugungsmitteln (M2; 25) mit einer elektronischen Schaltung, die
einen Komparator (25e) und einen ersten Musterspeicher (25a) aufweist, zur Erzeugung
das Halbtonbild darstellender binärer Bilddaten ansprechend auf einen Wert der Multidigitalbilddaten,
wobei der erste Musterspeicher (25a) erste Grundmusterdaten zur Punktausbildung, die
aus einer Anzahl von Schwellenwerten bestehen, speichert, wobei die Hardware-Punkterzeugungsmittel
(M2; 25) die Erzeugung durch Vergleichen der ersten Grundmusterdaten mit den Multidigitalbilddaten
mit dem Komparator (25e) für jedes Pixel durchführen,
(c) Software-Punkterzeugungsmitteln (M3) mit einer elektronischen Schaltung, die einen
zweiten Musterspeicher (17), einen Programmspeicher (17) und einen Prozessor (13)
aufweist, zur Erzeugung das Halbtonbild darstellender binärer Bilddaten ansprechend
auf einen Wert der Multidigitalbilddaten, wobei der zweite Musterspeicher zweite Grundmusterdaten
speichert, die aus Funktionsdaten bestehen, wobei der Programmspeicher ein Programm
zur Berechnung binärer Bilddaten auf der Grundlage von Multidigitalbilddaten und den
Funktionsdaten speichert, wobei der Prozessor das Programm zur Erzeugung binärer Bilddaten
ausführt, und
(d) Auswahlmitteln (M4) zum Auswählen der Hardware-Punkterzeugungsmittel (M2; 25)
oder der Software-Punkterzeugungsmittel (113) und Aktivieren der ausgewählten Mittel.
2. Vorrichtung nach Anspruch 1, wobei der erste Musterspeicher (25a) ein Nur-Lese-Speicher
und der zweite Musterspeicher ein Direktzugriff-Schreib-Lese-Speicher (17) ist.
3. Vorrichtung nach Anspruch 1, welche ferner
Dateneingabemittel zum Eingeben von Halbtonpunktartdaten, die eine Art von Halbtonpunkten
angeben, aufweisen und wobei
die Auswahlmittel
Beurteilungsmittel zum Beurteilen, ob die Halbtonpunktartdaten den ersten Grundmusterdaten
oder den zweiten Grundmusterdaten entsprechen, und
Mittel zur ausgewählten Aktivierung zum Aktivieren der Hardware-Punkterzeugungsmittel
(M2), wenn die Halbtonpunktartdaten den ersten Grundmusterdaten entsprechen, und Aktivieren
der Software-Punkterzeugungsmittel (M3), wenn die Halbtonpunktartdaten den zweiten
Grundmusterdaten entsprechen, aufweisen.
4. Vorrichtung nach Ansprüchen 1 bis 3, wobei
die ersten und zweiten Musterspeicher (25a, 17) mehrere Sätze von ersten Musterdaten
bzw. mehrere Sätze von zweiten Musterdaten speichern, und
die mit den Mitteln zur ausgewählten Aktivierung aktivierten Hardware- oder Software-Punkterzeugungsmittel
die Erzeugung von binären Bilddaten auf der Grundlage bezeichneter Musterdaten aus
den ersten und zweiten Musterspeichern (25a, 17), die mit den Halbtonpunktartdaten
bezeichnet sind, durchführen.
5. Vorrichtung gemäß Ansprüchen 1 bis 4, welche ferner
Bildbereichsspezifizierungsmittel zum Spezifizieren mehrerer Bildbereiche in dem Kontonbild
aufweist, und wobei
die Mittel zur ausgewählten Aktivierung die Hardware- oder Software-Punkterzeugungsmittel
(M2, M3) für jeden der mehreren Bildbereiche gemäß den Halbtonpunktartdaten, die jedem
der mehreren Bildbereiche zugeordnet sind, aktivieren.
6. Vorrichtung nach Ansprüchen 1 bis 5, welche ferner
Bildeditiermittel zum Editieren des ein Zeichen, eine Graphik und ein Bildelement
enthaltenden Kontonbilds, Erzeugen der das Kontonbild darstellenden multidigitalen
Bilddaten und Zuführen der multidigitalen Bilddaten an die Multidigitalbilddaten-Liefermittel,
Aufzeichnungsmittel zum Aufzeichnen eines Halbtonpunktbildes auf der Grundlage der
binären Bilddaten, die mit den Hardware-Punkterzeugungsmitteln (M2) oder Software-Punkterzeugungsmitteln
(M3) erzeugt worden sind, aufweist.
7. Vorrichtung gemäß Ansprüchen 1 und 6, wobei
die multidigitalen Bilddaten der Multidigitalbilddaten-Zuführmittel eine Seitenbeschreibungssprache,
die Orte, Richtungen und Größen von Zeichen, Graphik und Bildelement in dem Kontonbild
ausdrückt, enthalten.
8. Vorrichtung nach Ansprüchen 1, 6 und 7, wobei
die Multidigitalbilddaten-Liefermittel (M1) einen multidigitalen Bildspeicher enthalten.
9. Verfahren zur Ausbildung binärer Bilddaten eines Halbtonpunktbildes anhand multidigitaler
Bilddaten eines Kontonbildes mit den Schritten des
(a) Erstellens von das Kontonbild darstellenden Multidigitalbilddaten für jedes Pixel,
(b) Erstellens eines Hardware-Punktgenerators (M2; 25) mit einer elektronischen Schaltung,
welche einen Komparator (25e) und einen ersten Musterspeicher (25a) zur Speicherung
von ersten Grundmusterdaten zur Punktausbildung, bestehend aus einer Anzahl von Schwellenwerten,
aufweist, sowie eines Software-Punktgenerators (M3) mit einer elektronischen Schaltung,
welche einen Programmspeicher (17), einen Prozessor (13) und einen zweiten Musterspeicher
(17) zur Speicherung zweiter Musterdaten, bestehend aus Funktionsdaten, aufweist,
(c) Auswählens des Hardware-Punktgenerators (M2; 25) oder Software-Punktgenerators
(M3), und
(d) Aktivierens des ausgewählten Generators, wobei der Hardware-Punktgenerator (25)
die ersten Grundmusterdaten mit den Multidigitalbilddaten mit dem Komparator (25e)
für jedes Pixel zur Erzeugung binärer Bilddaten vergleicht, wenn der Hardware-Punktgenerator
(25) ausgewählt ist, und der Software-Punktgenerator (M3) das Halbtonbild darstellende
Binärbilddaten auf der Grundlage von Multidigitalbilddaten und den zweiten Musterdaten
mit dem Prozessor gemäß einem in dem Programmspeicher (17) gespeicherten Programm
berechnet, wenn der Software-Punktgenerator (M3) ausgewählt ist.
10. Verfahren nach Anspruch 9, wobei
der erste Musterspeicher (25a) ein Nur-Lese-Speicher und der zweite Musterspeicher
ein Direktzugriff-Schreib-Lese-Speicher (17) ist.
11. Verfahren nach Ansprüchen 9 und 10 mit, vor dem
Schritt (d), einem Schritt des
Eingebens von Halbtonpunktartdaten, die eine Art von Halbtonpunkten angeben, und wobei
der Schritt (d) die Schritte des
(d-1) Beurteilens, ob die Halbtonpunktartdaten den ersten Grundmusterdaten oder den
zweiten Grundmusterdaten entsprechen, und
(d-2) Aktivierens des Hardware-Punktgenerators (M2), wenn die Halbtonpunktartdaten
den ersten Grundmusterdaten entsprechen, und Aktivierens des Software-Punktgenerators
(M3), wenn die Halbtonpunktartdaten den zweiten Grundmusterdaten entsprechen, aufweist.
12. Verfahren nach Ansprüchen 9 bis 11, wobei
die ersten und zweiten Musterdaten mehrere Sätze von ersten Musterdaten und mehrere
Sätze von zweiten Musterdaten enthalten, und
in dem Schritt (d) ein aktivierter Punktgenerator (M2, M3) die Binärbilddaten auf
der Grundlage von bezeichneten Musterdaten aus den ersten und zweiten Musterdaten,
die durch die Halbtonpunktartdaten bezeichnet sind, erzeugt.
13. Verfahren nach Ansprüchen 9 bis 12, mit, zwischen den Schritten (b) und (c), einem
Schritt des
Spezifizierens mehrerer Bildbereiche in dem Konton-Bild, und wobei
in dem Schritt (d) der Hardware- oder Software-Punktgenerator (M2, M3) für jeden der
Anzahl von Bildbereiche gemäß den Halbtonpunktartdaten, die jedem der mehreren Bildbereiche
zugeordnet sind, aktiviert wird.
14. Verfahren nach Ansprüchen 9 bis 13, wobei
der Schritt (a) einen Schritt des Editierens des ein Zeichen, eine Graphik und ein
Bildelement enthaltenden Kontonbildes zur Erzeugung der Multidigitalbilddaten aufweist,
und
das Verfahren ferner einen Schritt des Aufzeichnens eines Halbtonpunktbildes auf der
Grundlage der Binärbilddaten, die durch den Hardware-Punktgenerator (M2) oder den
Software-Punktgenerator (M3) erzeugt worden sind, aufweist.
15. Verfahren nach Anspruch 14, wobei
die Multidigitalbilddaten eine Seitenbeschreibungssprache, die Orte, Richtungen
und Größen von Zeichen, Graphik und Bildelement in dem Kontonbild ausdrückt, enthalten.
1. Appareil pour former des données binaires d'image d'une image tramée en demi-teintes
en provenance de données multi-numériques d'une image en teintes continues comprenant
:
(a) des moyens de fourniture de données multi-numériques d'image (M1) pour fournir
des données multi-numériques d'image représentant ladite image en teintes continues
;
(b) des moyens matériels de production de trame (M2 ; 25) possédant un circuit électronique
comprenant un comparateur (25e) et une première mémoire de motif (25a) pour produire
des données binaires d'image représentant ladite image en demi-teintes en réponse
à un certain niveau desdites données multi-numériques d'image, ladite première mémoire
de motif (25a) stockant des premières données de motif de base, pour la formation
d'une trame, constituées par une pluralité de niveaux de seuil, lesdits moyens matériels
de production de trame (M2 ; 25) effectuant ladite production en comparant lesdites
premières données de motif de base auxdites données multi-numériques d'image à l'aide
dudit comparateur (25e) pour chaque élément d'image (pixel) ;
(c) des moyens logiciels de production de trame (M3) possédant un circuit électronique
comprenant une seconde mémoire de motif (17), une mémoire de programme (17) et un
processeur (13), pour produire des données binaires d'image représentant ladite image
en demi-teintes en réponse à un certain niveau desdites données multi-numériques d'image,
ladite seconde mémoire de motif stockant des secondes données de motif de base constituées
par des données de fonction, ladite mémoire de programme stockant un programme pour
calculer des données binaires d'image sur la base des données multi-numériques d'image
et desdites données de fonction, ledit processeur exécutant ledit programme pour produire
des données binaires d'image ; et
(d) des moyens de sélection (M4) pour sélectionner des moyens particuliers parmi lesdits
moyens matériels de production de trame (M2 ; 25) et lesdits moyens logiciels de production
de trame (M3), et pour activer les moyens sélectionnés.
2. Appareil selon la revendication 1, dans lequel
ladite première mémoire de motif (25a) est une mémoire à lecture seule, et ladite
seconde mémoire de motif (17) est une mémoire à accès direct.
3. Appareil selon la revendication 1, comprenant de plus :
des moyens d'entrée de données pour entrer des données du type points de trame indiquant
un type de trames en demi-teintes ; et dans lequel
lesdits moyens de sélection comprennent :
des moyens de détermination pour déterminer si lesdites données du type points de
trame correspondent auxdites premières données de motif de base ou auxdites secondes
données de motif de base ; et
des moyens d'activation sélective pour activer lesdits moyens matériels de production
de trame (M2) lorsque lesdites données du type points de trame correspondent auxdites
premières données de motif de base et pour activer lesdits moyens logiciels de production
de trame (M3) lorsque lesdites données du type points de trame correspondent auxdites
secondes données de motif de base.
4. Appareil selon les revendications 1 à 3, dans lequel
lesdites première et seconde mémoires de motif (25a, 17) stockent respectivement plusieurs
ensembles de premières données de motifs et plusieurs ensembles de secondes données
de motif ; et
des moyens particuliers, parmi lesdits moyens matériels et logiciels de production
de trame (M2, M3) activés par lesdits moyens d'activation sélective, effectuent ladite
production de données binaires d'image sur la base de données de motif désignées dans
lesdites première et seconde mémoires de motif (25a, 17) désignées par lesdites données
du type points de trame.
5. Appareil selon la revendication 1 à 4, comprenant de plus :
des moyens de spécification de zone d'image pour spécifier plusieurs zones d'image
dans ladite image en teintes continues ; et dans lequel
lesdits moyens d'activation sélective activent des moyens particuliers parmi lesdits
moyens matériels et logiciels de production de trame (M2, M3) pour chacune desdites
plusieurs zones d'image selon lesdites données du type points de trame attribuées
à chacune desdites plusieurs zones d'image.
6. Appareil selon les revendications 1 à 5, comprenant de plus :
des moyens d'édition d'image pour éditer ladite image en teintes continues comprenant
des caractères, des graphiques, et des éléments d'image, pour produire lesdites données
multi-numériques d'image représentant ladite image en teintes continues, et pour fournir
lesdites données multi-numériques d'image auxdits moyens de fourniture de données
multi-numériques d'image ; et
des moyens d'enregistrement pour enregistrer une image en demi-teintes sur la base
desdites données binaires d'image produites par des moyens particuliers parmi lesdits
moyens matériels de production de trame (M2) et lesdits moyens logiciels de production
de trame (M3).
7. Appareil selon les revendications 1 et 6, dans lequel
lesdites données multi-numériques d'image desdits moyens de fourniture de données
multi-numériques d'image comprennent un langage de description de page exprimant les
emplacements, les orientations, et les tailles desdits caractères, graphiques, et
éléments d'image dans ladite image en teintes continues.
8. Appareil selon les revendications 1, 6 et 7, dans lequel
lesdits moyens de fourniture de données multi-numériques d'image (M1) comprennent
une mémoire multi-numérique d'image.
9. Procédé de formation de données binaires d'image d'une image tramée en demi-teintes
en provenance de données multi-numériques d'une image en teintes continues comprenant
les étapes suivantes :
(a) la préparation de données multi-numériques d'image représentant ladite image en
teintes continues pour chaque élément d'image ;
(b) la préparation d'un générateur matériel de trame (M2 ; 25) possédant un circuit
électronique comprenant un comparateur (25e) et une première mémoire de motif (25a)
pour stocker des premières données de motif de base, pour la formation d'une trame,
constituées par une pluralité de niveaux de seuil, et d'un générateur logiciel de
trame (M3) possédant un circuit électronique comprenant un comparateur (17), un processeur
(13) et une seconde mémoire de motif (17) pour stocker des secondes données de motif
constituées par des données de fonction ;
(c) la sélection d'un générateur particulier parmi ledit générateur matériel de trame
(M2 ; 25) et ledit générateur logiciel de trame (M3) ; et
(d) l'activation du générateur sélectionné, de sorte que ledit générateur matériel
de trame (25) compare lesdites premières données de motif de base auxdites données
multi-numériques d'image à l'aide dudit comparateur (25e) pour chaque élément d'image
pour produire des données binaires d'image lorsque ledit générateur matériel de trame
(25) est sélectionné, et ledit générateur logiciel de trame (M3) calcule des données
binaires d'image représentant ladite image en demi-teintes sur la base de données
multi-numériques d'image et desdites secondes données de motif à l'aide dudit processeur
selon un programme stocké dans ladite mémoire de programme (17) lorsque ledit générateur
logiciel de trame (M3) est sélectionné.
10. Procédé selon la revendication 9, dans lequel
ladite première mémoire de motif (25a) est une mémoire à lecture seule, et ladite
seconde mémoire de motif (17) est une mémoire à accès direct.
11. Procédé selon les revendications 9 et 10, comprenant, avant ladite étape (d), une
étape de :
entrée de données du type points de trame indiquant un type de trames en demi-teintes
; et dans lequel
ladite étape (d) comprend les étapes suivantes :
(d-1) la détermination pour savoir si lesdites données du type points de trame correspondent
auxdites premières données de motif de base ou auxdites secondes données de motif
de base ; et
(d-2) l'activation dudit générateur matériel de trame (M2) lorsque lesdites données
du type points de trame correspondent auxdites premières données de motif de base
et l'activation dudit générateur logiciel de trame (M3) lorsque lesdites données du
type points de trame correspondent auxdites secondes données de motif de base.
12. Procédé selon les revendications 9 à 11, dans lequel
lesdites première et seconde données de motif comprennent respectivement plusieurs
ensembles de premières données de motifs et plusieurs ensembles de secondes données
de motif ; et
au niveau de ladite étape (d), un générateur activé de trame (M2, M3) produit lesdites
données binaires d'image sur la base de données de motif désignées dans lesdites première
et seconde données de motif désignées par lesdites données du type points de trame.
13. Procédé selon les revendications 9 à 12, comprenant, entre lesdites étapes (b) et
(c), une étape de :
spécification de plusieurs zones d'image dans ladite image en teintes continues ;
et dans lequel
au niveau de ladite étape (d), un générateur particulier parmi lesdits générateurs
matériel et logiciel de trame (M2, M3) est activé pour chacune desdites plusieurs
zones d'image selon lesdites données du type points de trame attribuées à chacune
desdites plusieurs zones d'image.
14. Procédé selon les revendications 9 à 13, dans lequel
ladite étape (a) comprend une étape d'édition de ladite image en teintes continues
comprenant des caractères, des graphiques, et des éléments d'image, pour produire
lesdites données multi-numériques d'image ; et
ledit procédé comprenant, de plus, une étape d'enregistrement d'une image en demi-teintes
sur la base desdites données binaires d'image produites par un générateur particulier
parmi ledit générateur matériel de trame (M2) et ledit générateur logiciel de trame
(M3).
15. Procédé selon la revendication 14, dans lequel
lesdites données multi-numériques d'image comprennent un langage de description
de page exprimant les emplacements, les orientations, et les tailles desdits caractères,
graphiques, et éléments d'image dans ladite image en teintes continues.